From e11bce7ad3e803e80883499fec0ad6e4540ffe43 Mon Sep 17 00:00:00 2001
From: Kristóf Marussy <marussy@mit.bme.hu>
Date: Tue, 30 Jun 2020 18:03:48 +0200
Subject: Add modified VIATRA-DSE version

---
 .../eclipse/viatra/dse/statecode/IStateCoder.java  | 82 ++++++++++++++++++++++
 .../viatra/dse/statecode/IStateCoderFactory.java   | 29 ++++++++
 2 files changed, 111 insertions(+)
 create mode 100644 Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoder.java
 create mode 100644 Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoderFactory.java

(limited to 'Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode')

diff --git a/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoder.java b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoder.java
new file mode 100644
index 00000000..f163f1a5
--- /dev/null
+++ b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoder.java
@@ -0,0 +1,82 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2014, Miklos Foldenyi, Andras Szabolcs Nagy, Abel Hegedus, Akos Horvath, Zoltan Ujhelyi and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.viatra.dse.statecode;
+
+import org.eclipse.emf.common.notify.Notifier;
+import org.eclipse.viatra.query.runtime.api.IPatternMatch;
+
+/**
+ * <p>
+ * To be able to efficiently explore a design space, a state that has been explored before through an other trajectory
+ * needs to be recognized and ignored accordingly.
+ * </p>
+ * 
+ * <p>
+ * This is done by generating a pseudo-unique value (object) that is only depended on the relevant parts of the model's
+ * internal state, that is, the values of two states can only be equal if the states themselves can be considered equal.
+ * </p>
+ * 
+ * <p>
+ * The processing engine however assumes, that any two states that share this pseudo-unique value has the same
+ * characteristics, meaning they have the same amount and type of outgoing transitions available, and firing the
+ * appropriate transitions from both states also result in states that share their pseudo-unique identifier. If this
+ * condition is not satisfied, the exploration process's result will be non-deterministic, and in consequence, solutions
+ * can be lost.
+ * </p>
+ * 
+ * <p>
+ * In addition to providing pseudo-unique identifiers to model states, the state coder must provide pseud-unique
+ * identifiers to the outgoing transitions as well, but they only need to be unique on the scope of the particular
+ * state, not globally. Global addressing thus can be achieved by considering the pseudo-unique identifier of the state
+ * and the pseudo-unique identifier of the transition together if needed.
+ * </p>
+ * 
+ * <p>
+ * Both identifiers can be arbitrary objects, and equality is checked by calling {@link Object#equals(Object)} on the
+ * two identifiers.
+ * </p>
+ * 
+ * <p>
+ * For any particular implementation an {@link IStateCoderFactory} implementation must also be supplied that handles the
+ * creation of {@link IStateCoder} instances.
+ * </p>
+ * 
+ * <p>
+ * Usually it is unnecessary to represent everything from the model in a state code, only the parts which are modified
+ * by the transformation rules.
+ * </p>
+ * 
+ * @author Miklos Foldenyi, Andras Szabolcs Nagy
+ * 
+ */
+public interface IStateCoder {
+
+    /**
+     * Initializes the state coder on the given model.
+     * 
+     * @param notifier
+     */
+    void init(Notifier notifier);
+
+    /**
+     * Returns a pseudo-unique identifier that describes the underlying model's current internal state.
+     * 
+     * @return an arbitrary {@link Object} that can be used as the identifier.
+     */
+    Object createStateCode();
+
+    /**
+     * Returns a pseudo-unique identifier that describes the given {@link IPatternMatch} in the context of the
+     * underlying model's current internal state.
+     * 
+     * @return an arbitrary {@link Object} that can be used as the identifier in the given state.
+     */
+    Object createActivationCode(IPatternMatch match);
+
+}
diff --git a/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoderFactory.java b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoderFactory.java
new file mode 100644
index 00000000..cf8bdf8d
--- /dev/null
+++ b/Solvers/VIATRA-Solver/org.eclipse.viatra.dse/src/org/eclipse/viatra/dse/statecode/IStateCoderFactory.java
@@ -0,0 +1,29 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2014, Miklos Foldenyi, Andras Szabolcs Nagy, Abel Hegedus, Akos Horvath, Zoltan Ujhelyi and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.viatra.dse.statecode;
+
+/**
+ * Interface for a factory class that creates instances of {@link IStateCoder} objects. This is required because state
+ * coders have to be created on-demand if the design space exploration process decides that a new thread is to be
+ * spawned. Since each thread requires it's own working model instance and a state coder is linked to the underlying
+ * model, a new {@link IStateCoder} needs to be created per processing thread.
+ * 
+ * @author Miklos Foldenyi, Andras Szabolcs Nagy
+ * 
+ */
+public interface IStateCoderFactory {
+
+    /**
+     * Creates a new {@link IStateCoder} instance specific to this {@link IStateCoderFactory}.
+     * 
+     * @return the new {@link IStateCoder} instance specific to this working model.
+     */
+    IStateCoder createStateCoder();
+
+}
-- 
cgit v1.2.3-70-g09d2